Earmark opponents may have scored some successes in recent years, but several Senators said they remain wary of permanently giving up the right to direct spending and would rather focus on other business.

"I think we need to talk about that," National Republican Senatorial Committee Chairman John Cornyn (R-Texas) said. "I am not sure we need it, but I am open to it."

He continued, "I wish we would focus on what the American people are most concerned about rather than some of these other issues that have their importance but are tangential to the main issues we ought to be focused on."

"I think we ought to [instead] be looking at other ways to ... address people's concerns about jobs and the debt," Cornyn said.

The Senate could vote this week on a proposal by Sens. Claire McCaskill (D-Mo.) and Pat Toomey (R-Pa.) to make the current moratorium on earmarks permanent. They've offered the measure as an amendment to legislation banning insider trading by lawmakers and their staff.

He said that while many earmarks are worthy of being funded, "There is an opportunity for corruption. A process like that is badly flawed and should be remedied."

The amendment would also create a point of order to strike earmarks from bills, and it would take two-thirds majority to override that point of order.

On the floor Tuesday, McCaskill said she wants to "stop the process in its entirety" rather than going after individual earmarks.

"I am proud of the fact that we have a moratorium," she said. "But there are a lot of Members of this body that want to go back to the old ways."

Still, earmark supporters said that the issue is purely political.

"It's just stupid, it's childish, it's demagoguery," Sen. James Inhofe (R-Okla.) said. "There is not a lot of courage in our conference [on the issue.] They all know better. They all know by banning earmarks ... they are just giving the authority to the president. But they are afraid of it because people don't understand the issue out there."

Sens. Mark Begich (D-Alaska), Dick Lugar (R-Ind.) and Ben Nelson (D-Neb.) said they would stand up to support their right to earmark if the amendment was brought to the Senate floor.

But it's unclear whether the amendment will get a vote.

"I hope we get a vote, but I am not optimistic," McCaskill said.

Senate Majority Leader Harry Reid (D-Nev.) on Tuesday would not say whether he would permit a vote on the proposal and gave a firm defense of earmarking.

"We'll see in a day or two how many are really interested in improving this bill, having amendments that are germane or relevant, and we'll take a look at it in a day or two," Reid said.

He added that he opposes an earmark ban. "We have an obligation as Members of Congress to fulfill our Constitutional duty. One of those duties is to make sure that we do Congressionally directed spending. I object and do not believe that all these decisions should be made at the White House," Reid said.

"I've done earmarks all my career, and I'm happy I've done earmarks my entire career," Reid continued. "They've helped my state and they helped different projects around the country. And I repeat, I will not stand by and be driven down this path that is one that I think is taking us away from what the Founding Fathers wanted: three separate but equal branches of government."

Sen. Richard Burr (R-N.C.), who backs a ban, said he doubts that it will pass even if it does come up for a vote.

"I am a co-sponsor of it," Burr said. "It's probably not going to pass. I think there is a lot of opposition to cutting off the gravy train on both sides of the aisle."

Earmarks make up less than 1 percent of overall federal spending.

Still, opponents of earmarks scored a victory after House Republicans won the majority in 2010 and voted soon after to adhere to a two-year moratorium, which expires at the end of this year.

The House's move forced Senate Democratic and Republican leaders' hands. Reid and Senate Minority Leader Mitch McConnell (R-Ky.) had been reluctant to curtail earmarks on Constitutional grounds. But Republicans agreed to a moratorium in November 2010, followed by Democrats in February 2011.

Some supporters of the moratorium, such as Sen. Lamar Alexander (R-Tenn.), even noted at the time that it was only supposed to be a temporary hiatus from the practice.

Earmarks also were tainted by relatively recent scandals. Last September, lobbyist Paul Magliocchetti, who headed the now-defunct lobby shop PMA Group, pleaded guilty in federal court to illegally funneling more than $386,000 in corporate campaign contributions to lawmakers, including appropriators, during a nearly six-year period.

Despite earmark opponents' successes in forcing leaders to accept a moratorium, the issue has had less success on the Senate floor.

In November 2010, the Senate voted 56-39 against an earmark ban McCaskill and Sen. Tom Coburn (R-Okla.) sought to attach to a food safety bill.